利用低轨卫星激光资料检验地球引力场模型的精度  

Evaluation of Gravitational Field Models Based on the Laser Range Observation of Low Earth Orbit Satellites

作　　者：汪宏波[1,2,3] 赵长印[1,2] 张伟[1,2] 旃进伟 喻圣贤[1,2] 

机构地区：[1]中国科学院紫金山天文台,南京210008 [2]中国科学院空间目标与碎片观测重点实验室,南京210008 [3]宇航动力学国家重点实验室,西安710043

出　　处：《天文学报》2015年第5期463-473,共11页Acta Astronomica Sinica

基　　金：宇航动力学国家重点实验室开放基金资助

摘　　要：地球引力场模型是人造卫星轨道计算中最重要的动力学模型之一.近年来国际上空间重力卫星计划取得了极大成功,相继推出了一系列新的引力场模型.从近地卫星轨道计算的角度检验了2种传统引力场模型(JGM3,EGM96)和4种新引力场模型(EIGENCHAMP05S,GGM03S,GOCE02S,EGM2008)的精度,利用4颗近地卫星的激光测距资料进行精密定轨预报,统计比较了不同模型的定轨残差和预报误差.结果表明:(1)4种新引力场模型精度基本在同一水平,对于近地卫星定轨精度普遍优于9 cm,最高达到5cm,相对于JGM3和EGM96模型有明显改善;(2)以JGM3模型为基准,EGM96模型的精度有所提高,2000年以后的4种新模型的精度则普遍提高了12%～47%(定轨)和63%(预报).70阶之前定轨精度随着模型阶次增大而提高,70阶以后定轨精度基本保持稳定,这表明对于近地卫星轨道计算而言,70阶的引力场已经能够满足厘米级的精度需求.The Earth gravitational filed model is a kind of important dynamic model in satellite orbit computation. In recent years, several space gravity missions have ob- tained great success, prompting a lot of gravitational filed models to be published. In this paper, 2 classical models （JGM3, EGM96） and 4 latest models, including EIGEN- CHAMP05S, GGM03S, GOCE02S, and EGM2008 are evaluated by being employed in the precision orbit determination （POD） and prediction, based on the laser range ob- servation of four low earth orbit （LEO） satellites, including CHAMP, GFZ-1, GRACE- A, and SWARM-A. The residual error of observation in POD is adopted to describe the accuracy of six gravitational field models. We show the main results as follows： （1） for LEO POD, the accuracies of 4 latest models （EIGEN-CHAMP05S, GGM03S, GOCE02S, and EGM2008） are at the same level, and better than those of 2 classical models （JGM3, EGM96）; （2） If taking JGM3 as reference, EGM96 model＇s accuracy is better in most situations, and the accuracies of the 4 latest models are improved by 12%-47% in POD and 63% in prediction, respectively. We also confirm that the model＇s accuracy in POD is enhanced with the increasing degree and order if they are smaller than 70, and when they exceed 70 the accuracy keeps stable, and is unrelated with the increasing degree, meaning that the model＇s degree and order truncated to 70 are sufficient to meet the requirement of LEO orbit computation with centimeter level precision.

关 键 词：天体力学 方法 数值 引力 轨道计算和定轨 

分 类 号：P135[天文地球—天体力学]